Creating Web Application + OAuth within Merge
Within the Active Azure Directory portal, navigate to "App Registration".
Register a new application for your Azure Active Directory Account
It is important to mark the application as "Web" and have the redirect URL filled in with the Merge OAuth Callback url!
For Merge Customers Only: In the Web Application, click on "Add a certificate or secret" and go through the steps to create an OAuth Client Secret.
For Merge Customers Only: Go to Azure Active Directory in Configurations, and click the box for being an Active Azure Directory Partner.
From here, you will leverage the Web Application you created earlier to fill in the Client ID (Application ID in Azure) and Client Secret.
The OAuth Redirect URL will be the Merge OAuth Callback URL that you can copy and paste.
The Directory (Tenant) ID will be used as the Subdomain when going through the Merge Linking Flow.